Anterior lens epithelium in cataract patients with retinitis pigmentosa - scanning and transmission electron microscopy study
Abstract
Purpose
In retinitis pigmentosa (RP) patients, relatively minor lens opacity posteriorly centrally may cause disproportionate functional symptoms requiring cataract operation. To investigate possible structural reasons for this opacity development, we studied the structure of the lens epithelium of RP patients.
Methods
The anterior lens capsule (aLC: basement membrane and associated LECs) were obtained from cataract surgery and prepared for scanning and transmission electron microscopy (SEM and TEM).
Results
Both SEM and TEM show the holes in the anterior lens epithelium of cataract patients with RP. Mainly, the holes appear as thinning and degradation of the epithelium, with the dimensions from less than 1 μm to more than 10 ηm and covering the region of several aLECs. A step towards the formation of denuded regions with the dimensions even bigger than 50 ηm may be the detachment of the lens epithelium. Other type of holes in size up to 20 ηm, may be formed by gradual stretching of the lens epithelium. Another type of holes is formed between adjacent LECs where lateral connections are absent, with dimensions 0.1-2 ηm × up to 10 ηm.
Conclusions
Showing of holes in the anterior lens epithelium supports the hypothesis that disturbed structure of the lens epithelium plays a role in water accumulation in the RP cataractous lens. We suggest that the lens epithelium has a role in the development of the cataract in RP patients.
